相关论文: Chemical and physical parameters from X-ray high r…
We present XMM-Newton observations of NCG891, a nearby edge-on spiral galaxy. We analyse the extent of the diffuse emission emitted from the disk of the galaxy, and find that it has a single temperature profile with best fitting temperature…
Recent observations found that electrons are accelerated to $\sim$10 GeV and emit synchrotron hard X-rays in two magnetic white dwarfs (WDs), also known as cataclysmic variables (CVs). In nova outbursts of WDs, multi-GeV gamma-rays were…
We present the analysis of multi-wavelength XMM-Newton data from the Seyfert galaxy NGC 3783, including UV imaging, X-ray and UV lightcurves, the 0.2-10 keV X-ray continuum, the iron K-alpha emission line, and high-resolution spectroscopy…
We present results from two XMM-Newton observations of the bright classical Seyfert 2 galaxy NGC 7582 taken four years apart (2001 May and 2005 April). We present the analysis of the high-resolution (0.3-1 keV) RGS and low-resolution…
We report on observations of the Galactic supernova remnant (SNR) G299.2$-$2.9 with the {\it Chandra X-Ray Observatory}. The high resolution images with {\it Chandra} resolve the X-ray-bright knots, shell, and diffuse emission extending…
We present BeppoSAX observations of Nova Velorum 1999 (V382 Vel), done in a broad X-ray band covering 0.1-300 keV only 15 days after the discovery and again after 6 months. The nova was detected at day 15 with the BeppoSAX instruments in…
We present the diffuse X-ray emission identified in Chandra observations of the young, massive Galactic star cluster Westerlund 1. After removing point-like X-ray sources down to a completeness limit of 2e31 erg/s, we identify 3e34 erg/s…
We measure the duty cycles for an existing sample of well observed, nearby dwarf novae using data from AAVSO, and present a quantitative empirical relation between the duty cycle of dwarf novae outbursts and the X-ray luminosity of the…
The initial results from XMM-Newton observations of the rich cluster of galaxies Abell 1795 are presented. The spatially-resolved X-ray spectra taken by the European Photon Imaging Cameras (EPIC) show a temperature drop at a radius of $\sim…
Nucleosynthesis in ONeMg novae has been investigated with the wide ranges of three parameters, i.e., the white dwarf mass, the envelope mass at ignition, and the initial composition. A quasi-analytic one-zone approach is used with an…
The high XMM-Newton throughput allows a detailed investigation of the spatial, spectral and variability properties of the extended and point source emission of the starburst galaxy NGC 253 simultaneously. We characterize the brightest…
White dwarfs experience a thermal renaissance when they receive mass from a stellar companion in a binary. For accretion rates < 10^-8 Msun/yr, the freshly accumulated hydrogen/helium envelope ignites in a thermally unstable manner that…
We report the discovery of X-ray emission at the position of the old classical nova DK Lacertae using the Swift satellite. Three observations were conducted using the X-ray telescope 62 years after the discovery of the nova, yielding 46…
We describe the highly variable X-ray and UV emission of V458 Vul (Nova Vul 2007), observed by Swift between 1 and 422 days after outburst. Initially bright only in the UV, V458 Vul became a variable hard X-ray source due to optically thin…
XMM-Newton observed the Seyfert 1.9 galaxy NGC 4258 in December 2000. At energies above 2 keV a hard nuclear point source is resolved that can be fitted by a highly absorbed power-law spectrum (NH = (8.0+-0.4)x10^22 cm^-2, photon index…
We present an X-ray study of our nearest starburst galaxy IC 10, based on XMM-Newton and Chandra observations. A list of 73 XMM-Newton and 28 Chandra detections of point-like X-ray sources in the field is provided; a substantial fraction of…
We study the 0509-67.5 supernova remnant in the Large Magellanic Cloud with the VLT/FORS2 spectrograph. We detect a broad component in the H-alpha emission with a FWHM of 2680 \pm 70 km/s and 3900 \pm 800 km/s for the southwest (SW) and…
We present time-dependent nova outburst models with optically thick winds for a 1.2 and 1.35 $M_\odot$ white dwarfs (WDs) with a mass accretion rate of $5 \times 10^{-9}~M_\odot$ yr$^{-1}$ and for a 1.3 $M_\odot$ WD with $2 \times…
Models of Galactic 1.275 MeV emission produced by the decay of the radionuclide $^{22}$Na have been computed. Several frequency-spatial distributions of novae have been investigated using recent results of nova rates and spatial…
The analyses of X-ray emission from classical novae during the outburst stage have shown that the soft X-ray emission below 1 keV, which is thought to originate from the photosphere of the white dwarf, is inconsistent with the simple…